Ni—Cr—Nb—P—B alloys capable of forming bulk metallic glass rods with diameters of 3 mm or greater have been disclosed in U.S. patent application Ser. No. 13/592,095, entitled “Bulk Nickel-Based Chromium and Phosphorus Bearing Metallic Glasses”, filed on Aug. 22, 2012, the disclosure of which is incorporated herein by reference in its entirety. In that application, a peak in glass forming ability is identified at chromium (Cr) content ranging from 8.5 to 9 atomic percent, niobium (Nb) content of about 3 atomic percent, boron (B) content ranging from 3 to 3.5 atomic percent, and phosphorus (P) content of about 16.5 atomic percent. Bulk metallic glass rods with diameters as large as 11 mm can be formed. However, the alloy forms a metallic glass which has a relatively low toughness at the peak of glass formability of the alloy.
Due to the attractive engineering properties of Ni-based P and B bearing bulk glasses, such as high strength, toughness, bending ductility, and corrosion resistance, there remains a need to develop alloys with various combinations of transition metals in order to explore the possibility of even better engineering performance, specifically higher toughness, while maintaining a high glass-forming ability.